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I'm getting ready to hire an electrical engineer for a small contract job - creating a prototype. What I'd like to know is, what should I have him deliver to me when the project is complete?

I imagine schematics, the prototype, parts list would be standard, but what am I missing? Should I ask for an auto-cad file - not sure what this is yet... Are there other things that I would need in the future for a different engineer to take over the project?

Simply, what should I be asking for?

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7 Answers 7

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Design engineers won't like the idea, but as a design engineer my output for a project is a pile of paper. In a strict sense the working prototype isn't even required, though it will certainly put the client's mind at ease. :-)
We'll see that you need a lot of documents, and design engineers are not motivated to the task; read: they tend to make a poor job of it. They're better at other things. Therefore some companies have a documentalist in a team, to follow up the documentation phase.

You need documents for every phase in the product's lifetime:

  • Production
  • Maintenance
  • Repair
  • Disposal

Production
This is the most extensive, and will get the most focus (and unfortunately it often stops there).

  • Schematics
  • PCB layout (Gerber files, including drill)
  • Bill of materials
  • Datasheets for all of the BOM(!)
  • Mechanical drawings
  • Software sources (incl. project file)
  • Software object files
  • Test jig design and operation instructions (this can include all the above files!)
  • ICP (In-Circuit Programming) procedure

Maintenance

  • Document(s) describing the procedure and tools for the product's maintenance, and how to replace consumables

Repair

  • Document(s) describing how the product has to be taken apart for replacing defective parts. Specifics about how to replace parts which may fail during the product's lifetime (based on FMEA. You did an FMEA, didn't you?)

Disposal

  • Document describing how the product has to be disposed of at it's end of life, with details about hazardous products and components.

Whenever possible documents should have a version number and/or issue date (you don't always have control over this, especially with external documents, though most datasheets will at least have either a version number or publishing date). You want all documents both in native format and in a standard electronic, printable format, like PDF. Specify how the electronic files have to be delivered: cloud (not a favorite of mine, confidentiality-wise), CD, DVD,...

As a note I want to say that especially in small projects even project management isn't often interested in anything else than schematics and PCB layout. Every one of these projects, without exception, runs into trouble later on.

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Assuming the engineer will be creating a printed circuit board (PCB), they will be using some sort of schematic capture and PCB layout program. You want to get a copy of his design files (not just the final output, such as a PDF of the schematic), so that they can be turned over to another engineer in the future if needed. Otherwise the second engineer would have to recreate the design files from the drawings.

For example, I use Eagle PCB, so the relevant files would be the schematic (.sch) and layout (.brd) files, along with any custom parts that I have added to a library (.lbr files). Also any unique design rule checks (.dru) and tooling files (.cam).

Although the Gerber files, which are sent to a board house to make the PCB, can be recreated from the design files, it would be a good idea to get a copy of those also.

There is no standard for the part-list (a.k.a a Bill of Materials, or BOM), but they are usually created using a spreadsheet such as Excel (.xls file). Make sure the engineer provides a source for each part, such as a Digi-Key part number.

If a prototype case is being made, for example with SolidWorks or other CAD software then you will want to get the relevant files for that as well.

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  • \$\begingroup\$ +1 for making sure the engineer provides a source for each part. \$\endgroup\$
    – semaj
    Commented Sep 27, 2010 at 15:28
  • \$\begingroup\$ As the person/company manufacturing the device it's YOUR responsibility to sign off on any parts that might be hard to find. Part of my responsibility is to make you aware of any potentially strange parts and get the ok from you to use them. No ok from you means that it's up to me to find another way to achieve the function of the unusual part. \$\endgroup\$
    – akohlsmith
    Commented Sep 27, 2010 at 18:04
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    \$\begingroup\$ I'm not fond of using a distibutor's part numbers, because they're too restricting. If you give the manufacturer's part number, you can go shopping wherever you like; the distri will always recognize it if he carries the part. \$\endgroup\$
    – stevenvh
    Commented Nov 1, 2011 at 11:46
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    \$\begingroup\$ @stevenvh, actually in the BOM I prepare, there are columns for manufacturer, manufacturer's part number, and Digi-Key part number. The reason I include the latter is to show that the part is actually available. If it's not in stock at Digi-Key, then I hunt down another source. \$\endgroup\$
    – tcrosley
    Commented Nov 1, 2011 at 12:30
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To add to the other descriptions, If your engineer uses Altium Designer, the file types are as follows:

*.PcbDoc - PCB File
*.SchDoc - Schematic File
*.PrjPcb - Logical project Grouping file. Not absolutely necessary, but nice to have.
*.PcbLib, *.SchLib, *.IntLib - PCB Library, Schematic library, and a baked-together library with both pcb and schematic primitives (note: if you get either a *.PcbLib AND *.SchLib, or just an *.IntLib, you're fine. they can be converted back and forth without issue).

All the DFM and DRC rules are packaged into the *.PcbDoc file, which is nice.

Getting the design files from your engineer is critical. I've recently been working on a project where the electrical design was farmed out, and no one knew what files they needed to get from the design house. Fast-forward a few years, and the design-house went out of business. and I'm stuck having to recreate the boards from the gerbers.

Maintenance is a nightmare without the proper files.

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Here is what I have typically delivered --

Initial Prototypes

Two functional prototypes. These boards may contain minor engineering changes but will be sufficient to verify functionality. It is expected that one revision of the design will be required.

Final Report

A design summary report that includes schematics, BOMs and component datasheets. All major design decisions are documented. Recommendations for future improvements are included. When I create the report I structure the BOM so that each line item in the BOM is a hyperlink to an embedded datasheet for the component.

Software Files

All application and library files.

EDA files

All EDA files for the first revision of the design.

Production PCB Files

If required, CAD files and manufacturing drawings to produce PCB panels will be provided.

Cost Estimates

Provide cost estimates for building multiple units.

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    \$\begingroup\$ This is something I would be much happier recieving than just schematic, PCB, and BOM information. Working prototypes + documented design decisions = much more comfort in whatever I'm delivering. EE work isn't just connect-the-dots. \$\endgroup\$ Commented Sep 27, 2010 at 19:46
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If they're in your hire, you should expect any designs they made while working for you, notes regarding their designs, any reports made during the process (incluing the final one), and pretty much anything else that related to the contract.

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    \$\begingroup\$ From my own experiences as a contractor I deliver schematics, layout files, component libraries, prototypes, gerbers, bills of material and "and any other design notes" upon confirmation of receipt of final payment. In other words, once the final payment clears the bank. If it's someone I've done work for before and we have an amiable relationship then it's not quite so strict. If I were you I would make sure that you don't just get "AutoCAD" copies of the schematics and layout files -- they're only useful for documentation. If you want to make changes, you'll need the real working files. \$\endgroup\$
    – akohlsmith
    Commented Sep 26, 2010 at 11:24
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    \$\begingroup\$ Andrew, This is a good answer. It should have been made as an actual answer and not just a comment. \$\endgroup\$
    – Kellenjb
    Commented Sep 27, 2010 at 1:33
  • \$\begingroup\$ Indeed; I was riffing off of pfyon's answer but realized later that my comment would have been better suited on its own instead of as a comment. \$\endgroup\$
    – akohlsmith
    Commented Sep 27, 2010 at 18:04
  • \$\begingroup\$ That is a good point. To be fair, the only experience I have with contracting is what we're told to expect from school. \$\endgroup\$
    – pfyon
    Commented Sep 28, 2010 at 18:04
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The deliverables should be clearly laid out in the contract, or at least a very good attempt should be made to do so. If both parties don't agree, rewrite the contract until they do, or move on. Avoid vague terms that mean whatever anybody wants them to, like "documentation". Include milestones, like a review and sign-off on a real specification document and test plan. The bigger and more involved, the more important to get the list of deliverables right. If you're nearing the end of a project, and you or your client aren't very sure about what will be handed over, your communication with your client could use some improvement. Good engineering + good commmunication = satisfied customer.

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Ask about test and troubleshooting too: eg. TP3 should be at 3.3V, TP4 at 5V, TP5 at 1Mhz clock. List of devices expected on JTAG scan chains. Software binaries and source code for any firmware.

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